This invention relates to a resiliently deformable safety covering tile, especially for floors, having a rigid base and a cover made of resiliently deformable material which includes a covering tile that is retained at a distance from the base and which possesses, on its underside only, a plurality of knob-like spacers which, being distributed essentially uniformly, rest loosely on the surface of the base. The covering tile has a continuous edge with a reentrantly directed bend by means of which it is anchored to the base. The base has a continuously stepped border formed with a continuous recess located on the side facing away from the covering tile, and the continuous edge of the covering tile, located outside the outline of the base, engages by means of its bend into the cutout portion of the base with a free space being provided under the bend of the continuous edge of the covering tile. Such safety covering tiles are used as ready-to-assemble floor parts preferably for small playing fields, as fall-protection floors in childrens' playgrounds and under games and sports equipment, and also in other leisure establishments. They can be laid on any foundation, for example in a sand bed, and also on a rough concrete floor or the like, with insulating material being interposed.
The invention evolves from a safety covering tile as is described in an as yet unpublished German application Serial No. P 31 06 784.0-25 of the present applicant. Here, a safety covering tile is provided in which a uniform force reduction is achieved over the entire tile and above and beyond its limits in a composite structure. The safety covering tile has the same or at least approximately the same deformability in all its regions. There is no anchoring of any kind between the inside of the covering tile or spacers and the surface of a base. Anchoring is maintained, on the one hand, by means of a continuous edge and a reentrantly directed bend on a stepped border, and knob-like spacers clearly separated in functional terms. In this way, anchoring no longer impedes the resiliently deformability of the covering tile. The continuous edge of the cover possesses, facing the particular tile adjacent to it, a vertically limiting face which extends from the region of spacers over much of the height of the base, so that when these safety covering tiles are laid in a composite structure these vertical faces of the individual tiles come to rest against one another. Because of the movability of the covers in relation to the bases, an undesirable corrugation of the surfaces of the covering tiles takes place during temperature changes as a result of different coefficients of expansion of the cover, on the one hand, and of the base, on the other hand. Especially when there is strong solar radiation on safety covering tiles laid closely up against one another in a composite structure, bulge-like arching of the individual covers is observed with the result that the entire surface becomes uneven.
Relevant safety covering tiles are also known from Great Britain Patent Specification No. 1,229,516 and from German Patent Specification No. 2,329,542. There, the existing covering tile portion of the cover is connected via anchoring bodies being arranged at intervals between the spacers and being anchored in the hardened material of the base. Moreover, these known safety covering tiles possess a continuous edge which rests on the top side of the base and thus forms an edge support. In these known safety covering tiles, the vertical side face of each tile is made continuous on the cover and on the base. When, as is customary, these tiles are laid without play in a composite structure, a temperature change results in comparatively pronounced corrugation and bulging, because, in addition, the air cushion retained between the cover and base is held sealed off by the edge resting on the base.
German Utility Model No. 70 13 835 shows a covering tile in which the cover is connected to the base via undercut portions. Here, there is no air cushion between the cover and the base, but the anchoring points and the continuous edge provided with a bend are anchored in the hardened material of the base. Here also, the tiles are limited on the four sides by vertically continuous faces. German Utility Model No. 76 09 345 shows a floor tile of similar design, but in this the covering tile is widened continuously round the side by means of shaped-on edge strips which serve the purpose of stamping the cover accurately to size after it has been produced, or of trimming the edge strips according to the dimensional accuracy required. Here too, the anchoring members and the continuous edge are shaped into the material of the base during the hardening of the latter. German Utility Model No. 77 24 504 shows a further development inasmuch as there are, here, on the underside of the covering tile spacers between which an air cushion can form. Here also, the continuous edge provided with the bend is anchored positively in the material of the base. The cover has, at the height of the covering tile, a continuous edge widening which projects in relation to the otherwise vertical limiting face. Such a design impedes the laying of the tiles in a composite structure inasmuch as the tiles with these edge widenings have to be laid up against one another so that the tiles have a plane surface at least at the laying temperature. However, even here there is a danger that the covers will exhibit the corrugation and bulging already described, especially in the case of strong solar radiation, because they are supported against one another in the region of the covering tile, and since the bend of the edge is shaped, the air cushion is also additionally enclosed and sealed off, and this expands accordingly under the effect of heat.
The corrugation and bulging described can be counteracted, in all events for covering tile of the type described in the introduction, by laying the individual tiles at a distance from one another, that is to say ensuring a continuous gap. Considerable care must be exercised to make these gaps uniform. Accessory devices, such as gap spacers, may be necessary here. In spite of these measures, which make the laying work more difficult, it may happen during the use of the floor covering that individual tiles change their relative positions in relation to the adjacent tiles and thereby butt against one another in the region of the gap so that corrugation and bulging can arise even here, though to a lesser extent.
An object of the invention is to provide safety covering tiles in which, on the one hand, can be laid easily and without additional aids and in which, on the other hand, corrugation and bulging are eliminated so that temperature effects do not cause a change in shape of the free surface of the tile covers.